Guacamaya chicks fetch between U.S. $100 and $650 in the black market for exotic pets, which has led to a bizarre situation: Poachers, called guaceros, stalk biologists to locate macaw nests.

Guacamayas nest 60 to 90 feet (18 to 27 meters) up in trees. Once the biologists finish a survey, the guacerosarmed with guns and climbing gearshinny up the trees and steal the fledglings.

"The guaceros are very aggressive, very well armed, and get the chicks no matter what," says Roan Balas McNab, a biologist with the New York-based Wildlife Conservation Society and the director of a 30-researcher team in the region.

The Guatemalan government assigned armed guards to protect the biologists. But in late April a guacero shot and wounded one of three guards accompanying a researcher. Just last week, another gang of guaceros ambushed researchers, who escaped. But McNab canceled one of the macaw projects.

The scarlet macaw is listed on Appendix I of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). Appendix I includes those species that are most endangered.

The northern Central American subspecies of scarlet macaw, Ara macao cyanoptera, has dwindled to a population of less than 1,000.

Guatemala's three key nesting sites are in the El Burral and El Peru regions of the Laguna del Tigre National Park and in the Sierra del Lacandón National Park. All the sites are within the 2.1 million hectare (8,100-square-mile) Maya Biosphere Reserve, the largest protected area in Central America, established in 1990 by the Guatemalan Congress.

Biologists Fight Fires, Chicks Vulnerable

Together El Peru and El Burrala new nesting site discovered by WCS biologists earlier this yearcontain about 80 percent of Macaw nests in the whole country.

"These birds are perched on the edge of extinction, but we still have time to strengthen the population," says McNab. "We need to solidify our presence in the area, and gain the support of the local communitynature will replenish herself."